1. Field of the Invention
The present invention relates to a method of selecting a tool in a punching press machine, and in particular to a method of selecting a tool in a punching press machine which is provided with a multi-tool holder including a plurality of punch tools.
2. Description of the Related Art
Conventional punching press machines are equipped with a magazine having a plurality of tool holders in which one punch tool is changeably mounted, so the punching press machines machine a workpiece by means of a punch tool which is selected from a plurality of punch tools according to indexing of the magazine and change the punch tool as occasion demands. When producing various products of a small amount, changing of the punch tools are frequently carried out, whereby productive efficiency lowers.
So, a multi-tool holder mounting a plurality of punch tools may be utilized. In a case of selecting a desired punch tool in this type of punching press machine, it is required to index the multi-tool holder as well as index the magazine. For this reason, conventionally, the amount of rotation of the magazine and multi-tool holder must be individually designated in machining programs. However, it is very troublesome to designate respective amounts of rotation of the magazine and the multi-tool holder each time when a selected punch tool is designated for selection, and it requires excess labor to make machining programs.